1. Field of the Invention
This invention relates to the field of hypodermic syringe holders for use in combination with disposable medicament-containing ampoules.
2. Description of the Prior Art
Disposable medicament-containing cartridge-needle units for use in conjunction with hypodermic syringe holders are well known in the art. Such cartridges conventionally feature a cylindrical body closed at the proximal end worth a flexible piston slidable within the bore of the cartridge and closed at the distal necked-down end with a diaphragm secured to the cartridge by a crimped-on metal collar. The necked-down distal end conventionally is fitted with a steel needle/needle hub unit and a needle sheath. Such needle/needle hub units have, minimally, a sharp end, typical of the type associated with hypodermic syringes.
Such cartridge-needle units can be used in conjunction with syringe holders which allow the user to avoid handling the cartridge-needle unit when the needle is exposed. Nevertheless, health care workers are especially susceptible to accidental and potentially infectious, and indeed, on occasion, possibly fatal, needle strikes due to careless handling and/or disposal of the cartridge-needle unit after use. The consequences to health care workers of strikes from needles contaminated with various infectious diseases such as hepatitis or AIDS can be particularly severe. The frequency of such accidental needle strikes in the United States is surprisingly great, and has been estimated to be approximately one million needle strikes per year. However, the cost to health care organizations for the testing of health care workers accidentally stricken by used needles is a significant burden on health care costs. Therefore, it would be desirable to further protect health care workers by providing medicament-containing cartridges without having to expose the user to the needle commonly associated with such cartridges.
In response to the "accidental needle strike" situation, numerous devices have been developed which allow the spent disposable medicament-containing ampoules to be removed from the holder without handling by the health care worker.
EPO case 0485028A1 describes a readily assembled, snap together hypodermic syringe holder. The body of the holder is a semi-cylindrical body. When the ampoule is to be ejected, the semi-cylindrical is positioned so its open side is faced downward. Gravity forces permit the ampoule to fall. The problem with this holder is that occasionally the ampoule is caught altering the trajectory of the ampoule's fall. This altering of the trajectory may cause "accidental needle strikes".
U.S. Pat. No. 5,028,698 describes an axial eject hypodermic syringe holder. This holder has a pair of pivotable jaws at the needle end of the holder. When the medicament-containing ampoule is to be removed from the holder and dropped by gravity into a disposal unit, the jaws are opened sufficiently to allow the ampoule to slidingly eject from the holder. The problem with this holder is the amount of parts required.
It would be highly desirable to provide a holder having a simplified and improved construction which allows for axial ejection of the ampoules.